China’s biggest oil firm, PetroChina, says it has made the country’s largest crude discovery in a decade. PetroChina said the find off China’s NE coast had proven reserves of almost three billion barrels. Western analysts said that while the field, called Jidong Nanpu, would probably produce less than a quarter of that amount, it was still a major find. Energy consultant Andrew Hayman of IHS said that under Western standards, Jidong Nanpu would probably have nearer to 650 million barrels of commercially recoverable reserves.